Just wanted to share my knowledge. This can be done by accessing the Postgres database of Tableau Server. The following query will show which users have deleted workbooks in the past 24 hours. Please note, this is not supported by Tableau, they will not be able to help modify or write queries against Postgres.

The following query should get what you're looking for. Please note, I removed the 24 hour filter via a comment. This can be added back if you'd like. Also note the Delete Type, you could create a filter on this to determine what kind of delete was done

I did notice a bug here though. If the view deleted from the workbook on the server was the last view of the workbook then the workbook gets dropped but this does NOT result in a 'Delete Workbook' event record. Any suggestions on how we could report this? I am guessing there is a long form way of keeping track of the count of views on the workbook before and after Delete View but that still is a function of investigation and not a reporting duty. Your thoughts...

If anyone is interested, I've been cultivating some pre-defined Tableau data sources that help answer server questions for Admins (and to the extent that they share this data, with users themselves): Shareable Data Sources for Tableau Server

One in particular, TS Events, will help answer these questions quickly and easily. Use the fields as shown below: